View Full Version : Idle speed adjustment, merc 240 EFI

07-31-09, 11:58 PM
The idle speed has gone down to where it wants to stall before I can shift it to reverse or forward and give it some throttle. Is the reduced idle speed an indication of something I need to look at?

I looked at service manual to see how to adjust idle and just got confused as to what exactly to adjust. How do you adjust idle or should I be looking at something else that is the cause?

08-01-09, 11:29 PM
The ECM should control that for you. If the problem started fairly suddenly start by changing the spark plugs.


08-02-09, 02:13 AM
I have had a problem starting my boat sometimes when it is warm. I discovered a trick to give the boat more gas when it is in nuetral. When you turn the steering wheel hard CCW or CW it will give the boat more gas. I don't know what the problem is though. On my boat I think the starter may be getting old.